Bennett’s wallaby in Tierpark Nordhorn, Germany.

Bennett’s wallaby in Tierpark Nordhorn, Germany.

Koala (Cracking the Koala Code - PBS)

Koala (Cracking the Koala Code - PBS)

A red kangaroo (Natural World - BBC)

A red kangaroo (Natural World - BBC)

Brush-tailed rock-wallaby (Secrets of our Living Planet - BBC)

Brush-tailed rock-wallaby (Secrets of our Living Planet - BBC)